Disappointing. As other reviewers have explained, this is an exploration of the isolationist- interventionist-debate prior to the US's entry into WWII. It is told primarily through the lens of Charles Lindbergh, famed aviator and international hero for his solo transatlantic flight and leader of the isolationist America First Committee, and FDR.
While I appreciate historians allowing historical figures to make their points in their own words, the author relies much too heavily on lengthy, verbatim regurgitations from Lindbergh's and Roosevelt's speeches and journals. Rarely, if ever, does the author provide any analysis, critique or even deeper context into the speakers' words. In a way, I found the author at times to be more stenographer than historian.
The lack of such analysis led me to feel that the author was too sympathetic to Lindbergh (which was likely not the author's intent). He spent extensive time on the enthusiasm Lindbergh unsurprisingly generated from his supporters, the crowd sizes at his speeches and the various meetings he held with various Congressmen in the isolationist camp while downplaying and failing to explore in any great detail Lindbergh's flirtation with, if not sympathy with, Nazis and antisemitism.
The same holds true of others who make quick appearances in the book, like, for instance, Henry Ford, George Sylvester and Avery Brundage With respect to Ford, the author spends as much time discussing a plane ride that Lindbergh gave Ford as does about Ford's virulent antisemitism, which did not seem to bother Lindbergh. Similar is his treatment of Viereck, a German-American writer who worked on behalf of Nazi Germany. The author simply quotes Viereck as stating (ridiculously) that antisemitism was not intrinsic to Nazism, but leaves it at that, without any further comment. And the author mentions that Brundage was an organizer of Lindbergh's speech on behalf of an organization called Citizens Committee to Keep America Out of War but fails to discuss Brundage's antisemitism. Similarly, the author quotes numerous Lindbergh speeches prior to his infamous and blatantly antisemitic Des Moines speech in which Lindbergh references "interests" looking to drag America into war but fails to consider who Lindbergh was referring to and, thus, whether these references to "interests" had antisemitic connotations.
Finally, the author provides very little context of what was actually going on in the world at the time that Lindbergh was arguing that the US was unprepared for war and had no real stake in it. He briefly mentions the Nazi conquests of Austria, Czechoslovakia and Poland and then France and Belgium in brief paragraphs, without discussing the absolute horrors that the people in these countries suffered after the Nazis gained control, the laws that were passed and the subsequent arrests, roundups, deportations and killings. Of course, the horrors of Hitler and the Nazis are well known, have been well covered elsewhere and aren't the main topic of this book and I did not expect it to be covered here in any great detail. But the failure to provide much of any context of what was going on while Lindbergh was urging isolationism made Lindbergh's arguments for why the US should stay out of the war more understandable than they otherwise would have been if the context was provided. The fact that the US may or may not have been safe from an actual foreign invasion -- Lindbergh's main argument for his isolationist views -- was not the full story.